The effects of polytetrafluoroethylene (PTFE) on the tensile and tribological properties of carbon fiber–reinforced poly(methyl methacrylate) (PMMA) composites were studied. Tribological tests were conducted on an Amsler friction and wear tester using a block-on-ring arrangement. It was observed that the PTFE played a main role in the tensile-resistant and wear-resistant properties of the PMMA composites. The tensile properties were ruled by the fiber–matrix adhesion. And the excellent tribological performance of the PTFE fillers improved the tribological properties of PMMA composites.